diff options
| author | Paul Durrant <Paul.Durrant@citrix.com> | 2017-03-02 13:54:26 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-03-03 18:36:15 +0100 |
| commit | a254d8f9a8a928772ef4608342125ccb35b79d5d (patch) | |
| tree | dda0845041f4823dd34c32ae1e974aeff896055d | |
| parent | xen-netback: keep a local pointer for vif in backend_disconnect() (diff) | |
| download | linux-a254d8f9a8a928772ef4608342125ccb35b79d5d.tar.xz linux-a254d8f9a8a928772ef4608342125ccb35b79d5d.zip | |
xen-netback: don't vfree() queues under spinlock
This leads to a BUG of the following form:
[ 174.512861] switch: port 2(vif3.0) entered disabled state
[ 174.522735] BUG: sleeping function called from invalid context at
/home/build/linux-linus/mm/vmalloc.c:1441
[ 174.523451] in_atomic(): 1, irqs_disabled(): 0, pid: 28, name: xenwatch
[ 174.524131] CPU: 1 PID: 28 Comm: xenwatch Tainted: G W
4.10.0upstream-11073-g4977ab6-dirty #1
[ 174.524819] Hardware name: MSI MS-7680/H61M-P23 (MS-7680), BIOS V17.0
03/14/2011
[ 174.525517] Call Trace:
[ 174.526217] show_stack+0x23/0x60
[ 174.526899] dump_stack+0x5b/0x88
[ 174.527562] ___might_sleep+0xde/0x130
[ 174.528208] __might_sleep+0x35/0xa0
[ 174.528840] ? _raw_spin_unlock_irqrestore+0x13/0x20
[ 174.529463] ? __wake_up+0x40/0x50
[ 174.530089] remove_vm_area+0x20/0x90
[ 174.530724] __vunmap+0x1d/0xc0
[ 174.531346] ? delete_object_full+0x13/0x20
[ 174.531973] vfree+0x40/0x80
[ 174.532594] set_backend_state+0x18a/0xa90
[ 174.533221] ? dwc_scan_descriptors+0x24d/0x430
[ 174.533850] ? kfree+0x5b/0xc0
[ 174.534476] ? xenbus_read+0x3d/0x50
[ 174.535101] ? xenbus_read+0x3d/0x50
[ 174.535718] ? xenbus_gather+0x31/0x90
[ 174.536332] ? ___might_sleep+0xf6/0x130
[ 174.536945] frontend_changed+0x6b/0xd0
[ 174.537565] xenbus_otherend_changed+0x7d/0x80
[ 174.538185] frontend_changed+0x12/0x20
[ 174.538803] xenwatch_thread+0x74/0x110
[ 174.539417] ? woken_wake_function+0x20/0x20
[ 174.540049] kthread+0xe5/0x120
[ 174.540663] ? xenbus_printf+0x50/0x50
[ 174.541278] ? __kthread_init_worker+0x40/0x40
[ 174.541898] ret_from_fork+0x21/0x2c
[ 174.548635] switch: port 2(vif3.0) entered disabled state
This patch defers the vfree() until after the spinlock is released.
Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/xen-netback/xenbus.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c index d82ddc913b4c..d2d7cd9145b1 100644 --- a/drivers/net/xen-netback/xenbus.c +++ b/drivers/net/xen-netback/xenbus.c @@ -496,6 +496,7 @@ static void backend_disconnect(struct backend_info *be) if (vif) { unsigned int queue_index; + struct xenvif_queue *queues; xen_unregister_watchers(vif); #ifdef CONFIG_DEBUG_FS @@ -508,11 +509,13 @@ static void backend_disconnect(struct backend_info *be) xenvif_deinit_queue(&vif->queues[queue_index]); spin_lock(&vif->lock); - vfree(vif->queues); + queues = vif->queues; vif->num_queues = 0; vif->queues = NULL; spin_unlock(&vif->lock); + vfree(queues); + xenvif_disconnect_ctrl(vif); } } |